Preheat oven to 180°C / 350°F.
Lightly grease a muffin tin or line it with paper muffin cups.
Peel and medium dice sweet potato.
Transfer sweet potato to a high speed blender or a large food processor. Add the rest of the ingredients, except for chocolate chips, and process until combined and smooth, stopping to scrap down the sides if necessary.
Fold in half of the chocolate chips.
Transfer batter to greased muffin tin, filling each cup 2/3 full.
Top muffins with the rest of the chocolate chips.
Bake for 25-30 minutes or until done (when an inserted stick comes out clean).
Let cool slightly and enjoy while warm, or let cool completely before storing in an airtight container!